The present invention relates to a steering column of a power vehicle, which can be height-adjusted by a manual force. More particularly, it relates to such a steeering column which has a telescopeable element with inner and outer tubes, and sliding bushes provided in an overlapping region of the inner tube with the outer tube and arranged at a distance from one another. In this steering column the flat sliding surfaces of the sliding bushes are associated with the sliding surfaces of the multi-cornered outer tube in the displacement region.
Manually height adjustable steering columns for power vehicles of the above mentioned general type are known in the art. One of such steering columns is disclosed, for example DE-OS 3,202,669. In this steering column the multicornered inner tube is provided with two injection molded or cast sliding bushes arranged at a distance from one another. The sliding surfaces of the sliding bushes coincide with one another and due to the manufacture in a joint casting or injection molding tool have low manufacturing tolerances which are independent from the manufacturing inaccuracies or manufacturing tolerances of the inner tube.
A part of the inner tube which lies between the sliding bushes is twisted during assembly, of the inner and outer tubes. Thereby, after the mounting of the telescopeable tubular element a force connection is produced between the outer and inner tubes. This connection insures a play-free condition between the parts of the telescopeable tubular element in the rotary direction of the steering column.
The sliding bushes which are mounted on the outer surface of the inner tube and arranged at such a distance from one another that an inner tube part is available between the sliding bushes can twist during assembling of the telescopeable element. Because of this, with a predetermined total length of the steering column, a correspondingly smaller displacement region between the outer tube and the inner tube is obtained.